Alignment means for mobile irrigation apparatus

ABSTRACT

A mobile irrigation apparatus formed of an elongate water distributing pipe having spaced sprinkling outlets and a plurality of laterally spaced apart mobile supports for movement of the distributing pipe over the land with means for maintaining substantial alignment between the supports during movement in one direction or the other.

Ririeet al.

1 1 Jan. 23,1973

1541 ALIGNMENT MEANS FOR MOBILE 2,604,359 7 1952 Zybach ..239/177IRRIGATION APPARATUS 2,941,727 6/1960 Zybach..... ...239/l77 l b h [75]Inventors: Max H. Ririe, Goring; Murray C. i both 3,381,894 5/1968Purtell ..239/212 x v scmtsbluffi Nebr- 3,417,766 12/1968 Purtell .239212 x [73] Assignee: Lockwood C0rp., Goring, Nebr.

' Primary Examiner-Lloyd L. King [22] Ffled' March Att0rneyMcDougall,Hersh & Scott [21] Appl. No.: 129,793

[57] ABSTRACT [52] U.S. Cl ..239/177, 239/212 A mobile irrigationapparatus formed of an elongate [51] Int. Cl. ..B05b 3/00 waterdistributing pipe having spaced sprinklin o t- Fleld of Search v letsand a plurality of laterally paced apart mobile I supports for movementof the distributing pipe .over [56] Reerences C'ted the land with meansfor maintaining substantial align- UNITED STATES PATENTS ment betweenthe supports during movement in one directlon or the other. 3,500,8563/1970 Boone et al ..239/l77 X 3,606,161 9/1971 Paul ..239/177 3 Claims,5 Drawing Figures PATENTEDJAH23 mm W 1 OF 2 3.712.544

maxwve rz Murray C. R land Rich Olson.

ALIGNMENT MEANS FOR MOBILE IRRIGATION APPARATUS This invention relatesto a self-propelled sprinkling system for large areas having a centralsource of water supply and it relates more particularly to a means formaintaining proper alignment of the self-propelled units embodied in thesystem.

Self-propelled sprinkling systems for irrigation of large areas are nowwell known. In a typical system, use is made of a main distributor pipewhich may be as much as mile in length, with the inner end portion ofthe pipe connected to a source of water for supply of water underpressure to sprinkling heads spaced along the length of the pipe fordispensing the water onto the crops in the field covered by thesprinkling system. The transmission pipe can be adapted to move acrossthe field in a substantially straight line but it is usually mounted forrotation about a central pivot where one end of the distributor pipe isconnected to the water supply. The distributor pipe is supported on aplurality of driven towers located at spaced intervals along the lengthof the distributor pipev and which operate to carry the pipe across thefield. Typical systems are illustrated in United States patents toZyback, U.S. Pat. No. 2,604,359; Behlen, U.S. Pat. No. 2,726,895; Boweret al. U.S. Pat. No. 3,394,729; Curtis, U.S. Pat. Nos. 3,352,403 and No.3,352,439, and Dowd, U.S. Pat. No.

In a system of the type described, it is important to minimize theamount of bending of the distributor pipe during its travel across thefield, whether traveling in a straight line or in a path which radiatesabout acentral pivot. Thus, it is desirable to maintain a semblence ofalignment between the self-propelled towers onwhich the distributor pipeis mounted'for support at longitudinally spaced points.

lt is an object of this invention to provide a selfpropelled irrigationsystem of the type described in which each of the intermediate mobilesupports or towers for the distributor pipe embody simple efficient andreliable means for self-alignment with others of the mobile supportsthereby to minimize the degree of misalignment between towers and/or thedegree of bend as well as the total accumulated bending of thetransmission pipe.

A further object of this invention is to provide a self propelledirrigation system of the type described which is effective to maintainproper alignments between the mobile support units and which can beadjusted in a simple and efficient manner to reverse the direction oftravel of the sprinkler system for operation over a segment of the areacapable of being covered by the system or to reverse the direction byreason of an obstruction lying in the path of the sprinkler system, suchas a wooded area, home, or the like.

These and other objects and advantages of this invention willhereinafter appear and, for purposes of illustration, but not-oflimitation, an embodiment of the invention is shown in the accompanyingdrawings in which:

P16. 1 is a perspective view of a self-propelled irrigation systemembodying the features of this invention, showing the pivot end and theouter end section with the intervening portions omitted;

FIG. 2 is a side elevational view of an intermediate mobile supporttower employed in the system of FlG. 1;

FIG. 3 is a diagrammatic view of the arrangement of elements for controlof the direction of movement of the intermediate carriers;

FIG. 4 is a perspective view showing in detail the control and switchoperation for the tower drive motor responsive to the location of theintermediate tower with respect to a control; and

FIG. 4 is a schematic elevational view of a modified form of alignmentcontrol.

The invention will be described with reference to an irrigation systemwherein the distributor pipe radiates about a central pivot but it willbe understood that the concepts for alignment control between the mobiletowers can be adapted in a system wherein the mobile support units areintended to travel in a straight line for unidirectional transport ofthe transmission line over all or a segment of the field. The inventionwill also be described with reference to the use as a control of theoutermost of the mobile units in which the driving motor is adaptedcontinuously to operate for movement of the outer mobile tower in theprescribed line of travel over the field but it will be understood thatone or more other mobile units may be used as the control. lt will beunderstood that the invention has application to sprinkling systems inwhich the distributor pipe is formed of a continuous section or ofseparate sections with flexible connections.

Referring now to the drawings for a description of the invention, thenumeral 10 indicates the elongate horizontally disposed waterdistribution pipe which is provided with a swivel connection 12 at itsinner end for pivotal attachment to the upper end of a feed pipe 14which may extend downwardly to a well in the ground or which isotherwise supplied with water under pressure for irrigation, as from astream, well or other source of water. Thus the feed pipe 14 representsthe axis about which the water distributor pipe turns. Other means forpivotal attachment in sealing engagement between the distributor pipeand the feed pipe are well known by reason of the widespread utilizationof such an arrangement in commercial practice, as illustrated in theaforementioned patents.

The distributor pipe 10 is provided with a plurality of spray nozzles 16at frequently spaced intervals along the length of the pipe foroperation as overhead sprays to sprinkle water onto the crop as thedistributor pipe moves about the feed as its axis. The distributor pipeis supplied with water under pressure, as by means of a water pumpconnected with a supply pipe or water tower.

A number of mobile towers T are arranged in longitudinally spaced apartrelation along the length of the distributor pipe with means forengaging the adjacent portions of the pipe for support. The number ofmobile towers T can be varied depending somewhat upon the spacedrelationship between supports and the length of the distributor pipe.The distributor pipe 10 can be suspended from the support by means of acable so as to be carried by the support. lt can rest on the tower as ona cradle rigidly secured to the support but, in accordance with thepreferred practice of this invention, the distributor pipe 10 is rigidlyconnected with the support tower as by means of suitable straps l8 andstruts 20.

The mobile tower is not a critical element of the invention since mobiletowers of various constructions generally employed in the trade may beused. As a result, while the invention will be described with referenceto a representative tower assembly, it will be understood that towers ofdifferent structures may be used.

Each mobile tower is of substantially the same construction such thatonly one such representative mobile tower need be described in detail.Referring to FIG. 2 of the drawings, the mobile tower includes avertically disposed A frame formed of legs 22 and 24 with bearingsprovided at their lower end portions having journals for receiving stubshafts 26 and 28 on which land-engaging wheels 30 and 32 respectivelyare mounted for wheeled support of the tower.

The legs 22 and 24 of the A frame are braced by one or more cross bracemembers 34 and as well as struts 36 and 38 to provide a rigid structureof high structural strength. Supported between the cross brace memberson the A frame is an electrical driving motor 40 which is operativelyconnected to a speed reducer 42, as by means of a driving belt or chain44 which operates about a sprocket 46 on the end of the motor shaft andanother sprocket 48 on the ingoing shaft of the speed reducer. The speedreducer is connected to the land-engaging wheels 30 and 32 for thetransmission of rotational movement to the wheels. in the illustratedmodification such transmission from the speed reducer to the wheels iseffected by means of a sprocket 46 mounted for free rotational movementon the cross brace member 34 of the A frame and which is adapted to bedriven by the speed reducer through a chain 49 trained about a spur gear50 fixed to the outgoing end of the speed reducer shaft and sprocket 46.A shaft 52 rigid with the sprocket 46 is operatively connected to thewheel 30 through a driving chain 54 having one end trained about a spurgear on the shaft 52 while the other end is trained about the sprocket56 fixed to the stub shaft 26 on which the wheel 30 is mounted. Thewheel 32 is similarly driven for rotational movement in the samedirection as by means ofa chain 58 trained about another spur gear onthe shaft 52 and a sprocket 60 fixed to the shaft on which the wheel 32is mounted.

The driving motor 40 is a reversible motor so that the mobile tower canbe interchangeably driven in one direction or the other. Thus,responsive to rotation of the motor in one direction, the reducing gear42 will be turned in one direction to cause the land-engaging wheels toboth turn in the same direction and propel the mobile tower over theground. Reversal ofthe driving motor will cause the land-engaging wheelto turn in the opposite direction together to reverse the directionofmovement ofthe mobile towers.

Thus the direction of tower movement (forward or reverse) is controlledby the direction of rotation of the driving motor (clockwise orcounterclockwise). Motor rotation is, in turn, determined by therespective phase relation of the electrical power. The motor 40 isenergized by the operation of the magnetic motor starter MS and isprotected from accidental overload and subsequent damage by the overloadcurrent devices such as overload heater coils of the magnetic motorstarter. The alignment switch, hereinafter described, controls theoperation of the magnetic motor starter and subsequently the movement ofthe tower itself.

In the illustrated modification, the motor 40 is a three phase motorconnected to a three phase power supply including phase lines A, B andC, while the magnetic motor starter is controlled via the alignmentswitch 82 by the control power lines identified in the drawings as thecommon neutral line N, reverse control line R, and forward control lineF.

in the preferred construction, the driving motor on the outermost towerT0 is connected for continuous or intermittent operation, depending ondesired operational speed, in one direction or the other, as selected bythe operator or by suitable switching mechanisms. Operation of thedriving motors of the intermediate towers depends upon the relativeposition of the intermediate towers with respect to the outer tower asthe control.

In accordance with an important concept of this invention, suchautomatic alignment means comprises a flexible cable 62 which is fixedat its inner end 64 to an arm 66 which extends laterally from the pivotwhile the outer end 68 is fixed to the end portion ofa laterallyextending cross beam 70 on the outermost tower so that the flexiblecable 62 will extend in essentially a straight line from said pivot tosaid outermost tower.

The flexible cable is threaded through an opening 72 in a pendulum 74that is mounted on each of the intermediate towers for free rockingmovement about an axis 76 which is parallel with the axis of the pipeand in a direction crosswise of the distributor pipe. As illustrated inFIGS. 2 and 4, the pendulum 74 comprises an elongate member which issuspended to depend from the tower on a pivot pin 78 extending laterallyfrom the end portion of a horizontally disposed cross brace member 80rigid with the tower. The pendulum is supported on the tower at a levelhigh enough to enable the flexible cable easily to clear the crops sothat the growing crops will not interfere with the function of the cableas an alignment control. An electrical switch 82 is fixed to the crossbrace member 80 with the plunger positioned in the pathway of theswinging pendulum 74. Instead of making use ofa pendulum for support ofthe flexible cable, the intermediate portions of the flexible cable canbe supported on slide bars extending crosswise between the switchmembers whereby reliance will be had on the cable itself to make orunmake the switch as it slides laterally over the supporting surface.

As illustrated in FIG. 3, the common line N is connected to one terminalof the magnetic motor starter while the forward control line isconnected to one pole of the switch which, when the switch is closed,establishes connection with the other pole of the relay to effectoperation for forward movement of the tower arid which, when open,disengagcs the forward control I wire from the magnetic motor starter tostop operation Thus, when the intermediate mobile tower is in properalignment, the pendulum will be suspended from its pivot to hangdownwardly substantially perpendicularly so that the pendulum will befree of the plunger of switch 82 as well as the plunger of switch 84.

When the forward control line F is the hot line for forward movement ofthe mobile tower and the pendulum hangs downwardly out of engagementwith the plunger 83 of the switch 82, a voltage is applied between theforward control line F and the common or neutral wire N, with the switchin the normally closed (NC) position. The three-phase power is energizedwith the phase relation A-B-C to effect operation for correspondingforward movement of the mobile tower along with the outermost tower. Aslong as alignment continues and the pendulum 74 hangs free of theplunger 83 of switch 82, the motor 40 will continue to operate to effectforward movement of the tower.

If the particular tower advances to a position of misalignment, thecable will cause the pendulum to rock about its pivot in the clockwisedirection until the pendulum engages the plunger. Engagement of theplunger operates to open the switch 82 and disconnect the forwardcontrol line F from the neutral common control line to terminate thepassage of voltage therebetween. This causes an interruption in themagnetic motor starter circuit and the driving motor 40 is de-energized.

Operation of the motor and forward movement of the mobile tower will bethus discontinued as long as the pendulum engages the plunger 83 to makethe switch. As the outer tower continues to move forwardly, while theintermediate tower is stationary, the cable will move forwardly with theouter mobile unit ultimately to cause the pendulum to rock forwardlyabout its pivot into a position out of engagement with the plunger 83.This will occur when the outer mobile unit reaches substantial alignmentwith the stopped intermediate mobile tower. This will release theplunger for return of the switch to NC position whereby the drivingmechanism will commence operation again to effect forward movement ofthe intermediate mobile tower with the continued forward movement of theouter control unit. f This sequence will repeat as often as is necessaryto keep the tower in-line with the other respective towers.

lf reverse operation is desired, a voltage is applied between thereverse control wire (R) and the common or neutral (N). The three-phasemotor is energized with the phase relation CB-A. This change inrelationship will cause the driving motor to run in the reversedirection.

When operating in the reverse direction the switch is in the normallyopen position (NO) whereby a circuit is established between the reversecontrol wire R and the neutral N to cause operation of the driving motorin the reverse direction. This situation will continue as long as thetower is in-line so that the pendulum hangs free of the plunger 85. Asthe tower'advances beyond the adjacent towers or beyond the outercontrol tower, the control cable causes the pendulum to rock in thecounterclockwise direction about its pivot until it engages the plunger85 and breaks the circuit when the out-ofalignment becomes excessive.

This breaks the circuit between the line R and N to discontinueoperation of the motor.

As the adjacent towers or outer control tower catch up to bring aboutthe in-line arrangement, the pendulum swings clockwise to release theplunger 85 for return of the switch to normal open position forreenergization of the motor with corresponding reverse movement of thetower.

This sequence will repeat as often as is necessary to keep the towerin-line with the other respective towers.

It will be apparent that the direction of travel is controlled by therespective phase relationship of the elec trical supply. It will also beapparent that a voltage is applied to the proper control wire whichcorresponds to the'desired direction of travel.

It will be apparent that the motors of the intermediate towers willoperate to effect movement of the intermediate towers in one directionor the other when the intermediate tower is in substantial alignmentwith adjacent towers and in-line with the outer control tower and thatthe driving motor of any intermediate tower will automatically cease tooperate in response to movement of the intermediate tower beyond theposition of the control cable in the direction of movement. The distanceat which such controls become effective to effect stopping and startingof the driving motors may be varied but, in the preferred practice, itis desirable to stop the operation of the driving motor of anintermediatetower when the tower advances out of alignment by an amountcorresponding to 2 to 10 feet.

It will be understood that the assembly may include other elements suchas safety control which operates to discontinue all of the electricalcircuits in the event that a motor fails to operate and a tower lags toofar behind or in the event that a motor continues to operate out ofcontrol whereby the intermediate tower travels too far ahead. Suchadditional additional controls and elements have not been described inthis application which is addressed primarily to the control means foralignment of mobile towers in normal operation.

It will be apparent that the direction of movement of the mobile towersand their supported distributor pipe can be reversed merely by reversalto make one or the other of the control lines F or R the hot line withthe common or neutral line N, and the independent reversal of thedriving motor. Such reversal operation can be controlled by switch meansto reverse their direction when the traveling irrigation system hastraversed a predetermined segment of the area capable of being coveredor to reverse the direction to avoid an obstruction such as a house,barn, trees or the like.

It will be understood that changes may be made in the details ofconstruction and arrangement without departing from the spirit of theinvention, especially as defined in the following claims.

We claim:

1. A mobile irrigation apparatus comprising an elongate horizontallydisposed water distributing pipe, an inlet at one end for theintroduction of water under pressure, a plurality of discharge nozzlesspaced along said distributing pipe between its ends for spraying wateras the distributing pipe is carried over the land, a main mobile supportadjacent the other end of the distributing pipe and means mounting aportion of the distributing pipe thereon for support and for movementtherewith, a plurality of intermediate mobile supports in laterallyspaced apart relation along the length of the distributing pipe betweenthe inlet end and the main mobile support for support of thedistributing pipe at corresponding laterally spaced apart portions,individual motor drive means on each support for actuation of the mobilesupports individually for movement in the forward or rearwarddirections, means for maintaining alignment between the intermediatesupports and the main support during continuous operation of the mainsupport in the forward or rearward direction comprising a flexible cableextending substantially parallel to the distributing pipe from the inletend to the main support and attached thereto, means on each intermediatesupport for controlling operation of the motor drive means on therespective intermediate support. and switch means having switchoperating elements in position to be responsive to the cable todiscontinue operation of the drive means in response to movement of theintermediate support out of alignment with the main or adjacent supportsto a position a predetermined distance in advance in the direction ofmovement of the main support to discontinue operation of the poweroperated drive means and to initiate operation of the motor drive meansresponsive to return of the intermediate support into position ofalignment whereby it continues to travel with the main support in thedirection of movement thereof while in alignment therewith.

2. A mobile irrigation apparatus as claimed in claim 1 in which theinlet end of the distributing pipe represents a pivotal point aboutwhich the distributing pipe circulates as it is carried by the main andintermediate supports.

3. A mobile irrigation apparatus as claimed in claim 1 in which eachintermediate support includes a pendulum suspended from a pivot fixed tothe support for free rocking movement of the pendulum about an axisparallel with the axis of the distributing pipe and in a directioncorresponding to the movement of the support, an opening in a portion ofthe pendulum offset from the pivot through which an intermediate portionof the flexible cable extends for effecting rocking movement of thependulum responsive to movement of the support relative to adjacentsupports and the main support, and switch operating means in the path ofmovement of the pendulum to effect operation of the switch meansresponsive to movement of said pendulum.

1. A mobile irrigation apparatus comprising an elongate horizontallydisposed water distributing pipe, an inlet at one end for theintroduction of water under pressure, a plurality of discharge nozzlesspaced along said distributing pipe between its ends for spraying wateras the distributing pipe is carried over the land, a main mobile supportadjacent the other end of the distributing pipe and means mounting aportion of the distributing pipe thereon for support and for movementtherewith, a plurality of intermediate mobile supports in laterallyspaced apart relation along the length of the distributing pipe betweenthe inlet end and the main mobile support for support of thedistributing pipe at corresponding laterally spaced apart portions,individual motor drive means on each support for actuation of the mobilesupports individually for movement in the forward or rearwarddirections, means for maintaining alignment between the intermediatesupports and the main support during continuous operation of the mainsupport in the forward or rearward direction comprising a flexible cableextending substantially parallel to the distributing pipe from the inletend to the main support and attached thereto, means on each intermediatesupport for controlling operation of the motor drive means on therespective intermediate support, and switch means having switchoperating elements in position to be responsive to the cable todiscontinue operation of the drive means in response to movement of theintermediate support out of alignment with the main or adjacent supportsto a position a predetermined distance in advance in the direction ofmovement of the main support to discontinue operation of the poweroperated drive means and to initiate operation of the motor drive meansresponsive to return of the intermediate support into position ofalignment whereby it continues to travel with the main support in thedirection of movement thereof while in alignment therewith.
 2. A mobileirrigation apparatus as claimed in claim 1 in which the inlet end of thedistributing pipe represents a pivotal point about which thedistributing pipe circulates as it is carried by the main andintermediate supports.
 3. A mobile irrigation apparatus as claimed inclaim 1 in which each intermediate support includes a pendulum suspendedfrom a pivot fixed to the support for free rocking movement of thependulum about an axis parallel with the axis of the distributing pipeand in a direction corresponding to the movement of the support, anopening in a portion of the pendulum offset from the pivot through whichan intermediate portion of the flexible cable extends for effectingrocking movement of the pendulum responsive to movement of the supportrelative to adjacent supports and the main support, and switch operatingmeans in the path of movement of the pendulum to effect operation of theswitch means responsive to movement of said pendulum.